//download.js v3.0, by dandavis; 2008-2014. [CCBY2] see http://danml.com/download.html for tests/usage
// v1 landed a FF+Chrome compat way of downloading strings to local un-named files, upgraded to use a hidden frame and optional mime
// v2 added named files via a[download], msSaveBlob, IE (10+) support, and window.URL support for larger+faster saves than dataURLs
// v3 added dataURL and Blob Input, bind-toggle arity, and legacy dataURL fallback was improved with force-download mime and base64 support

// data can be a string, Blob, File, or dataURL
(()=>{
	window.download=function(data, strFileName, strMimeType) {
	
		var self = window, // this script is only for browsers anyway...
			u = "application/octet-stream", // this default mime also triggers iframe downloads
			m = strMimeType || u, 
			x = data,
			D = document,
			a = D.createElement("a"),
			z = function(a){return String(a);},
			
			
			B = self.Blob || self.MozBlob || self.WebKitBlob || z,
			BB = self.MSBlobBuilder || self.WebKitBlobBuilder || self.BlobBuilder,
			fn = strFileName || "download",
			blob, 
			b,
			ua,
			fr;
	
		//if(typeof B.bind === 'function' ){ B=B.bind(self); }
		
		if(String(this)==="true"){ //reverse arguments, allowing download.bind(true, "text/xml", "export.xml") to act as a callback
			x=[x, m];
			m=x[0];
			x=x[1]; 
		}
		
		
		
		//go ahead and download dataURLs right away
		if(String(x).match(/^data\:[\w+\-]+\/[\w+\-]+[,;]/)){
			return navigator.msSaveBlob ?  // IE10 can't do a[download], only Blobs:
				navigator.msSaveBlob(d2b(x), fn) : 
				saver(x) ; // everyone else can save dataURLs un-processed
		}//end if dataURL passed?
		
		try{
		
			blob = x instanceof B ? 
				x : 
				new B([x], {type: m}) ;
		}catch(y){
			if(BB){
				b = new BB();
				b.append([x]);
				blob = b.getBlob(m); // the blob
			}
			
		}
		
		
		
		window.d2b=function(u) {
			var p= u.split(/[:;,]/),
			t= p[1],
			dec= p[2] == "base64" ? atob : decodeURIComponent,
			bin= dec(p.pop()),
			mx= bin.length,
			i= 0,
			uia= new Uint8Array(mx);
	
			for(i;i<mx;++i) uia[i]= bin.charCodeAt(i);
	
			return new B([uia], {type: t});
		 }
		  
		 window.saver=function (url, winMode){
			
			
			if ('download' in a) { //html5 A[download] 			
				a.href = url;
				a.setAttribute("download", fn);
				a.innerHTML = "downloading...";
				D.body.appendChild(a);
				setTimeout(function() {
					a.click();
					D.body.removeChild(a);
					if(winMode===true){setTimeout(function(){ self.URL.revokeObjectURL(a.href);}, 250 );}
				}, 66);
				return true;
			}
			
			//do iframe dataURL download (old ch+FF):
			var f = D.createElement("iframe");
			D.body.appendChild(f);
			if(!winMode){ // force a mime that will download:
				url="data:"+url.replace(/^data:([\w\/\-\+]+)/, u);
			}
			 
		
			f.src = url;
			setTimeout(function(){ D.body.removeChild(f); }, 333);
			
		}//end saver 
			
	
		if (navigator.msSaveBlob) { // IE10+ : (has Blob, but not a[download] or URL)
			return navigator.msSaveBlob(blob, fn);
		} 	
		
		if(self.URL){ // simple fast and modern way using Blob and URL:
			saver(self.URL.createObjectURL(blob), true);
		}else{
			// handle non-Blob()+non-URL browsers:
			if(typeof blob === "string" || blob.constructor===z ){
				try{
					return saver( "data:" +  m   + ";base64,"  +  self.btoa(blob)  ); 
				}catch(y){
					return saver( "data:" +  m   + "," + encodeURIComponent(blob)  ); 
				}
			}
			
			// Blob but not URL:
			fr=new FileReader();
			fr.onload=function(e){
				saver(this.result); 
			};
			fr.readAsDataURL(blob);
		}	
		return true;
	} /* end download() */
	
})();						 
						 
